[geary] (14 commits) ...Merge branch 'wip/search-fixes' into 'mainline'

[Michael Gratton <mjog src gnome org>]

Summary of changes:

  ebc3b99... Make ConversationMonitor's Fill op use local-only initially (*)
  52e558f... Explicitly flag when ConversationMonitor Fill op is done (*)
  7cf9825... Make ImapDb.SearchQuery prepare terms at construction time (*)
  983e8ce... Mark Geary.Account.open_search as async and throwing an err (*)
  f9ba7a0... Remove unused code (*)
  b4a04f8... Use a single RO transaction when removing matches from a se (*)
  abdcfc8... Execute ConversationMonitor ops in batches to avoid UI stal (*)
  e56908a... Append unknown conversations since it may be re-constituted (*)
  4d18b7b... Only insert email into the conversation monitor when needed (*)
  3786725... Bump ConversationMonitor op batch size right up (*)
  d9c2a96... Use a list when producing search results to preserve orderi (*)
  389f31d... Fix search including results from spam, trash and drafts (*)
  724450c... Minor source code formatting improvements (*)
  e65d45f... Merge branch 'wip/search-fixes' into 'mainline'

(*) This commit already existed in another branch; no separate mail sent